Fused Deposition Modeling (FDM) technology is a heated material extrusion additive manufacturing (AM) process that uses thermoplastics. FDM is a manufacturing process used to produce three dimensional (3D) conceptual models, prototypes and production parts. FDM can be referred to as 3D printing. In the FDM process, a thermoplastic filament is driven into a liquefier to produce a semi-molten plastic. The semi-molten plastic is extruded through a small diameter heated extrusion nozzle while the heated extrusion nozzle scans a horizontal plane and is selectively deposited onto a build platform to produce a cross section or layer. The build platform is lowered after the completion and thermal fusion of each later until the all layers have been fabricated, meaning FDM of the object is complete. FDM technology is used to fabricate or print individual piece-parts (namely, a part usually manufactured using a machining process).
A missile seeker includes optical elements, detectors, and electronics fixed within a mechanical housing. A military entity uses several types of missile seekers. For example, the missile seekers can have housings of different dimensions and different shapes or profiles. The missile seekers can use the same subcomponents. The various shaped missile seekers can use a common set of optical elements, mechanical and electrical parts. For manufacture of a missile seeker, the housing unique to each type of missile seeker must be procured. Each optical, mechanical or electrical components manually placed into the housing and secured in place by screws, by fasteners, by torqueing, by retainers, or by adhesive bonding. For example, the bottom of one lens is placed atop a ledge of the bottom portion of a lens barrel, and then adhesive bonding material is dispensed atop the lens to mechanically hold the lens in place in the housing.
The missile seeker manufacturing facility must keep an inventory of various housings for each type of missile seeker that the military entity may purchase. In response to a military entity purchase order, the missile seeker manufacturing facility must reconfigure its assembly line machinery and retrain assembly line workers (also referred to as employees) for the type of missile seeker requested. Machine reconfiguration and training employees generate lead time between the time the military entity requests a particular type of missile seeker and the start time of manufacturing the first requested missile seeker. Training employees impacts the risk of error in assembly and quality control, but does not prevent manufacturing variances amount caused by innate imprecision of human capital.